xref: /openbmc/linux/drivers/char/ipmi/ipmi_devintf.c (revision 12eb4683)
1 /*
2  * ipmi_devintf.c
3  *
4  * Linux device interface for the IPMI message handler.
5  *
6  * Author: MontaVista Software, Inc.
7  *         Corey Minyard <minyard@mvista.com>
8  *         source@mvista.com
9  *
10  * Copyright 2002 MontaVista Software Inc.
11  *
12  *  This program is free software; you can redistribute it and/or modify it
13  *  under the terms of the GNU General Public License as published by the
14  *  Free Software Foundation; either version 2 of the License, or (at your
15  *  option) any later version.
16  *
17  *
18  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
19  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
20  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
24  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
25  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
26  *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
27  *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  *  You should have received a copy of the GNU General Public License along
30  *  with this program; if not, write to the Free Software Foundation, Inc.,
31  *  675 Mass Ave, Cambridge, MA 02139, USA.
32  */
33 
34 #include <linux/module.h>
35 #include <linux/moduleparam.h>
36 #include <linux/errno.h>
37 #include <linux/poll.h>
38 #include <linux/sched.h>
39 #include <linux/spinlock.h>
40 #include <linux/slab.h>
41 #include <linux/ipmi.h>
42 #include <linux/mutex.h>
43 #include <linux/init.h>
44 #include <linux/device.h>
45 #include <linux/compat.h>
46 
47 struct ipmi_file_private
48 {
49 	ipmi_user_t          user;
50 	spinlock_t           recv_msg_lock;
51 	struct list_head     recv_msgs;
52 	struct file          *file;
53 	struct fasync_struct *fasync_queue;
54 	wait_queue_head_t    wait;
55 	struct mutex	     recv_mutex;
56 	int                  default_retries;
57 	unsigned int         default_retry_time_ms;
58 };
59 
60 static DEFINE_MUTEX(ipmi_mutex);
61 static void file_receive_handler(struct ipmi_recv_msg *msg,
62 				 void                 *handler_data)
63 {
64 	struct ipmi_file_private *priv = handler_data;
65 	int                      was_empty;
66 	unsigned long            flags;
67 
68 	spin_lock_irqsave(&(priv->recv_msg_lock), flags);
69 
70 	was_empty = list_empty(&(priv->recv_msgs));
71 	list_add_tail(&(msg->link), &(priv->recv_msgs));
72 
73 	if (was_empty) {
74 		wake_up_interruptible(&priv->wait);
75 		kill_fasync(&priv->fasync_queue, SIGIO, POLL_IN);
76 	}
77 
78 	spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
79 }
80 
81 static unsigned int ipmi_poll(struct file *file, poll_table *wait)
82 {
83 	struct ipmi_file_private *priv = file->private_data;
84 	unsigned int             mask = 0;
85 	unsigned long            flags;
86 
87 	poll_wait(file, &priv->wait, wait);
88 
89 	spin_lock_irqsave(&priv->recv_msg_lock, flags);
90 
91 	if (!list_empty(&(priv->recv_msgs)))
92 		mask |= (POLLIN | POLLRDNORM);
93 
94 	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
95 
96 	return mask;
97 }
98 
99 static int ipmi_fasync(int fd, struct file *file, int on)
100 {
101 	struct ipmi_file_private *priv = file->private_data;
102 	int                      result;
103 
104 	mutex_lock(&ipmi_mutex); /* could race against open() otherwise */
105 	result = fasync_helper(fd, file, on, &priv->fasync_queue);
106 	mutex_unlock(&ipmi_mutex);
107 
108 	return (result);
109 }
110 
111 static struct ipmi_user_hndl ipmi_hndlrs =
112 {
113 	.ipmi_recv_hndl	= file_receive_handler,
114 };
115 
116 static int ipmi_open(struct inode *inode, struct file *file)
117 {
118 	int                      if_num = iminor(inode);
119 	int                      rv;
120 	struct ipmi_file_private *priv;
121 
122 
123 	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
124 	if (!priv)
125 		return -ENOMEM;
126 
127 	mutex_lock(&ipmi_mutex);
128 	priv->file = file;
129 
130 	rv = ipmi_create_user(if_num,
131 			      &ipmi_hndlrs,
132 			      priv,
133 			      &(priv->user));
134 	if (rv) {
135 		kfree(priv);
136 		goto out;
137 	}
138 
139 	file->private_data = priv;
140 
141 	spin_lock_init(&(priv->recv_msg_lock));
142 	INIT_LIST_HEAD(&(priv->recv_msgs));
143 	init_waitqueue_head(&priv->wait);
144 	priv->fasync_queue = NULL;
145 	mutex_init(&priv->recv_mutex);
146 
147 	/* Use the low-level defaults. */
148 	priv->default_retries = -1;
149 	priv->default_retry_time_ms = 0;
150 
151 out:
152 	mutex_unlock(&ipmi_mutex);
153 	return rv;
154 }
155 
156 static int ipmi_release(struct inode *inode, struct file *file)
157 {
158 	struct ipmi_file_private *priv = file->private_data;
159 	int                      rv;
160 
161 	rv = ipmi_destroy_user(priv->user);
162 	if (rv)
163 		return rv;
164 
165 	/* FIXME - free the messages in the list. */
166 	kfree(priv);
167 
168 	return 0;
169 }
170 
171 static int handle_send_req(ipmi_user_t     user,
172 			   struct ipmi_req *req,
173 			   int             retries,
174 			   unsigned int    retry_time_ms)
175 {
176 	int              rv;
177 	struct ipmi_addr addr;
178 	struct kernel_ipmi_msg msg;
179 
180 	if (req->addr_len > sizeof(struct ipmi_addr))
181 		return -EINVAL;
182 
183 	if (copy_from_user(&addr, req->addr, req->addr_len))
184 		return -EFAULT;
185 
186 	msg.netfn = req->msg.netfn;
187 	msg.cmd = req->msg.cmd;
188 	msg.data_len = req->msg.data_len;
189 	msg.data = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL);
190 	if (!msg.data)
191 		return -ENOMEM;
192 
193 	/* From here out we cannot return, we must jump to "out" for
194 	   error exits to free msgdata. */
195 
196 	rv = ipmi_validate_addr(&addr, req->addr_len);
197 	if (rv)
198 		goto out;
199 
200 	if (req->msg.data != NULL) {
201 		if (req->msg.data_len > IPMI_MAX_MSG_LENGTH) {
202 			rv = -EMSGSIZE;
203 			goto out;
204 		}
205 
206 		if (copy_from_user(msg.data,
207 				   req->msg.data,
208 				   req->msg.data_len))
209 		{
210 			rv = -EFAULT;
211 			goto out;
212 		}
213 	} else {
214 		msg.data_len = 0;
215 	}
216 
217 	rv = ipmi_request_settime(user,
218 				  &addr,
219 				  req->msgid,
220 				  &msg,
221 				  NULL,
222 				  0,
223 				  retries,
224 				  retry_time_ms);
225  out:
226 	kfree(msg.data);
227 	return rv;
228 }
229 
230 static int ipmi_ioctl(struct file   *file,
231 		      unsigned int  cmd,
232 		      unsigned long data)
233 {
234 	int                      rv = -EINVAL;
235 	struct ipmi_file_private *priv = file->private_data;
236 	void __user *arg = (void __user *)data;
237 
238 	switch (cmd)
239 	{
240 	case IPMICTL_SEND_COMMAND:
241 	{
242 		struct ipmi_req req;
243 
244 		if (copy_from_user(&req, arg, sizeof(req))) {
245 			rv = -EFAULT;
246 			break;
247 		}
248 
249 		rv = handle_send_req(priv->user,
250 				     &req,
251 				     priv->default_retries,
252 				     priv->default_retry_time_ms);
253 		break;
254 	}
255 
256 	case IPMICTL_SEND_COMMAND_SETTIME:
257 	{
258 		struct ipmi_req_settime req;
259 
260 		if (copy_from_user(&req, arg, sizeof(req))) {
261 			rv = -EFAULT;
262 			break;
263 		}
264 
265 		rv = handle_send_req(priv->user,
266 				     &req.req,
267 				     req.retries,
268 				     req.retry_time_ms);
269 		break;
270 	}
271 
272 	case IPMICTL_RECEIVE_MSG:
273 	case IPMICTL_RECEIVE_MSG_TRUNC:
274 	{
275 		struct ipmi_recv      rsp;
276 		int              addr_len;
277 		struct list_head *entry;
278 		struct ipmi_recv_msg  *msg;
279 		unsigned long    flags;
280 
281 
282 		rv = 0;
283 		if (copy_from_user(&rsp, arg, sizeof(rsp))) {
284 			rv = -EFAULT;
285 			break;
286 		}
287 
288 		/* We claim a mutex because we don't want two
289                    users getting something from the queue at a time.
290                    Since we have to release the spinlock before we can
291                    copy the data to the user, it's possible another
292                    user will grab something from the queue, too.  Then
293                    the messages might get out of order if something
294                    fails and the message gets put back onto the
295                    queue.  This mutex prevents that problem. */
296 		mutex_lock(&priv->recv_mutex);
297 
298 		/* Grab the message off the list. */
299 		spin_lock_irqsave(&(priv->recv_msg_lock), flags);
300 		if (list_empty(&(priv->recv_msgs))) {
301 			spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
302 			rv = -EAGAIN;
303 			goto recv_err;
304 		}
305 		entry = priv->recv_msgs.next;
306 		msg = list_entry(entry, struct ipmi_recv_msg, link);
307 		list_del(entry);
308 		spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
309 
310 		addr_len = ipmi_addr_length(msg->addr.addr_type);
311 		if (rsp.addr_len < addr_len)
312 		{
313 			rv = -EINVAL;
314 			goto recv_putback_on_err;
315 		}
316 
317 		if (copy_to_user(rsp.addr, &(msg->addr), addr_len)) {
318 			rv = -EFAULT;
319 			goto recv_putback_on_err;
320 		}
321 		rsp.addr_len = addr_len;
322 
323 		rsp.recv_type = msg->recv_type;
324 		rsp.msgid = msg->msgid;
325 		rsp.msg.netfn = msg->msg.netfn;
326 		rsp.msg.cmd = msg->msg.cmd;
327 
328 		if (msg->msg.data_len > 0) {
329 			if (rsp.msg.data_len < msg->msg.data_len) {
330 				rv = -EMSGSIZE;
331 				if (cmd == IPMICTL_RECEIVE_MSG_TRUNC) {
332 					msg->msg.data_len = rsp.msg.data_len;
333 				} else {
334 					goto recv_putback_on_err;
335 				}
336 			}
337 
338 			if (copy_to_user(rsp.msg.data,
339 					 msg->msg.data,
340 					 msg->msg.data_len))
341 			{
342 				rv = -EFAULT;
343 				goto recv_putback_on_err;
344 			}
345 			rsp.msg.data_len = msg->msg.data_len;
346 		} else {
347 			rsp.msg.data_len = 0;
348 		}
349 
350 		if (copy_to_user(arg, &rsp, sizeof(rsp))) {
351 			rv = -EFAULT;
352 			goto recv_putback_on_err;
353 		}
354 
355 		mutex_unlock(&priv->recv_mutex);
356 		ipmi_free_recv_msg(msg);
357 		break;
358 
359 	recv_putback_on_err:
360 		/* If we got an error, put the message back onto
361 		   the head of the queue. */
362 		spin_lock_irqsave(&(priv->recv_msg_lock), flags);
363 		list_add(entry, &(priv->recv_msgs));
364 		spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
365 		mutex_unlock(&priv->recv_mutex);
366 		break;
367 
368 	recv_err:
369 		mutex_unlock(&priv->recv_mutex);
370 		break;
371 	}
372 
373 	case IPMICTL_REGISTER_FOR_CMD:
374 	{
375 		struct ipmi_cmdspec val;
376 
377 		if (copy_from_user(&val, arg, sizeof(val))) {
378 			rv = -EFAULT;
379 			break;
380 		}
381 
382 		rv = ipmi_register_for_cmd(priv->user, val.netfn, val.cmd,
383 					   IPMI_CHAN_ALL);
384 		break;
385 	}
386 
387 	case IPMICTL_UNREGISTER_FOR_CMD:
388 	{
389 		struct ipmi_cmdspec   val;
390 
391 		if (copy_from_user(&val, arg, sizeof(val))) {
392 			rv = -EFAULT;
393 			break;
394 		}
395 
396 		rv = ipmi_unregister_for_cmd(priv->user, val.netfn, val.cmd,
397 					     IPMI_CHAN_ALL);
398 		break;
399 	}
400 
401 	case IPMICTL_REGISTER_FOR_CMD_CHANS:
402 	{
403 		struct ipmi_cmdspec_chans val;
404 
405 		if (copy_from_user(&val, arg, sizeof(val))) {
406 			rv = -EFAULT;
407 			break;
408 		}
409 
410 		rv = ipmi_register_for_cmd(priv->user, val.netfn, val.cmd,
411 					   val.chans);
412 		break;
413 	}
414 
415 	case IPMICTL_UNREGISTER_FOR_CMD_CHANS:
416 	{
417 		struct ipmi_cmdspec_chans val;
418 
419 		if (copy_from_user(&val, arg, sizeof(val))) {
420 			rv = -EFAULT;
421 			break;
422 		}
423 
424 		rv = ipmi_unregister_for_cmd(priv->user, val.netfn, val.cmd,
425 					     val.chans);
426 		break;
427 	}
428 
429 	case IPMICTL_SET_GETS_EVENTS_CMD:
430 	{
431 		int val;
432 
433 		if (copy_from_user(&val, arg, sizeof(val))) {
434 			rv = -EFAULT;
435 			break;
436 		}
437 
438 		rv = ipmi_set_gets_events(priv->user, val);
439 		break;
440 	}
441 
442 	/* The next four are legacy, not per-channel. */
443 	case IPMICTL_SET_MY_ADDRESS_CMD:
444 	{
445 		unsigned int val;
446 
447 		if (copy_from_user(&val, arg, sizeof(val))) {
448 			rv = -EFAULT;
449 			break;
450 		}
451 
452 		rv = ipmi_set_my_address(priv->user, 0, val);
453 		break;
454 	}
455 
456 	case IPMICTL_GET_MY_ADDRESS_CMD:
457 	{
458 		unsigned int  val;
459 		unsigned char rval;
460 
461 		rv = ipmi_get_my_address(priv->user, 0, &rval);
462 		if (rv)
463 			break;
464 
465 		val = rval;
466 
467 		if (copy_to_user(arg, &val, sizeof(val))) {
468 			rv = -EFAULT;
469 			break;
470 		}
471 		break;
472 	}
473 
474 	case IPMICTL_SET_MY_LUN_CMD:
475 	{
476 		unsigned int val;
477 
478 		if (copy_from_user(&val, arg, sizeof(val))) {
479 			rv = -EFAULT;
480 			break;
481 		}
482 
483 		rv = ipmi_set_my_LUN(priv->user, 0, val);
484 		break;
485 	}
486 
487 	case IPMICTL_GET_MY_LUN_CMD:
488 	{
489 		unsigned int  val;
490 		unsigned char rval;
491 
492 		rv = ipmi_get_my_LUN(priv->user, 0, &rval);
493 		if (rv)
494 			break;
495 
496 		val = rval;
497 
498 		if (copy_to_user(arg, &val, sizeof(val))) {
499 			rv = -EFAULT;
500 			break;
501 		}
502 		break;
503 	}
504 
505 	case IPMICTL_SET_MY_CHANNEL_ADDRESS_CMD:
506 	{
507 		struct ipmi_channel_lun_address_set val;
508 
509 		if (copy_from_user(&val, arg, sizeof(val))) {
510 			rv = -EFAULT;
511 			break;
512 		}
513 
514 		return ipmi_set_my_address(priv->user, val.channel, val.value);
515 		break;
516 	}
517 
518 	case IPMICTL_GET_MY_CHANNEL_ADDRESS_CMD:
519 	{
520 		struct ipmi_channel_lun_address_set val;
521 
522 		if (copy_from_user(&val, arg, sizeof(val))) {
523 			rv = -EFAULT;
524 			break;
525 		}
526 
527 		rv = ipmi_get_my_address(priv->user, val.channel, &val.value);
528 		if (rv)
529 			break;
530 
531 		if (copy_to_user(arg, &val, sizeof(val))) {
532 			rv = -EFAULT;
533 			break;
534 		}
535 		break;
536 	}
537 
538 	case IPMICTL_SET_MY_CHANNEL_LUN_CMD:
539 	{
540 		struct ipmi_channel_lun_address_set val;
541 
542 		if (copy_from_user(&val, arg, sizeof(val))) {
543 			rv = -EFAULT;
544 			break;
545 		}
546 
547 		rv = ipmi_set_my_LUN(priv->user, val.channel, val.value);
548 		break;
549 	}
550 
551 	case IPMICTL_GET_MY_CHANNEL_LUN_CMD:
552 	{
553 		struct ipmi_channel_lun_address_set val;
554 
555 		if (copy_from_user(&val, arg, sizeof(val))) {
556 			rv = -EFAULT;
557 			break;
558 		}
559 
560 		rv = ipmi_get_my_LUN(priv->user, val.channel, &val.value);
561 		if (rv)
562 			break;
563 
564 		if (copy_to_user(arg, &val, sizeof(val))) {
565 			rv = -EFAULT;
566 			break;
567 		}
568 		break;
569 	}
570 
571 	case IPMICTL_SET_TIMING_PARMS_CMD:
572 	{
573 		struct ipmi_timing_parms parms;
574 
575 		if (copy_from_user(&parms, arg, sizeof(parms))) {
576 			rv = -EFAULT;
577 			break;
578 		}
579 
580 		priv->default_retries = parms.retries;
581 		priv->default_retry_time_ms = parms.retry_time_ms;
582 		rv = 0;
583 		break;
584 	}
585 
586 	case IPMICTL_GET_TIMING_PARMS_CMD:
587 	{
588 		struct ipmi_timing_parms parms;
589 
590 		parms.retries = priv->default_retries;
591 		parms.retry_time_ms = priv->default_retry_time_ms;
592 
593 		if (copy_to_user(arg, &parms, sizeof(parms))) {
594 			rv = -EFAULT;
595 			break;
596 		}
597 
598 		rv = 0;
599 		break;
600 	}
601 
602 	case IPMICTL_GET_MAINTENANCE_MODE_CMD:
603 	{
604 		int mode;
605 
606 		mode = ipmi_get_maintenance_mode(priv->user);
607 		if (copy_to_user(arg, &mode, sizeof(mode))) {
608 			rv = -EFAULT;
609 			break;
610 		}
611 		rv = 0;
612 		break;
613 	}
614 
615 	case IPMICTL_SET_MAINTENANCE_MODE_CMD:
616 	{
617 		int mode;
618 
619 		if (copy_from_user(&mode, arg, sizeof(mode))) {
620 			rv = -EFAULT;
621 			break;
622 		}
623 		rv = ipmi_set_maintenance_mode(priv->user, mode);
624 		break;
625 	}
626 	}
627 
628 	return rv;
629 }
630 
631 /*
632  * Note: it doesn't make sense to take the BKL here but
633  *       not in compat_ipmi_ioctl. -arnd
634  */
635 static long ipmi_unlocked_ioctl(struct file   *file,
636 			        unsigned int  cmd,
637 			        unsigned long data)
638 {
639 	int ret;
640 
641 	mutex_lock(&ipmi_mutex);
642 	ret = ipmi_ioctl(file, cmd, data);
643 	mutex_unlock(&ipmi_mutex);
644 
645 	return ret;
646 }
647 
648 #ifdef CONFIG_COMPAT
649 
650 /*
651  * The following code contains code for supporting 32-bit compatible
652  * ioctls on 64-bit kernels.  This allows running 32-bit apps on the
653  * 64-bit kernel
654  */
655 #define COMPAT_IPMICTL_SEND_COMMAND	\
656 	_IOR(IPMI_IOC_MAGIC, 13, struct compat_ipmi_req)
657 #define COMPAT_IPMICTL_SEND_COMMAND_SETTIME	\
658 	_IOR(IPMI_IOC_MAGIC, 21, struct compat_ipmi_req_settime)
659 #define COMPAT_IPMICTL_RECEIVE_MSG	\
660 	_IOWR(IPMI_IOC_MAGIC, 12, struct compat_ipmi_recv)
661 #define COMPAT_IPMICTL_RECEIVE_MSG_TRUNC	\
662 	_IOWR(IPMI_IOC_MAGIC, 11, struct compat_ipmi_recv)
663 
664 struct compat_ipmi_msg {
665 	u8		netfn;
666 	u8		cmd;
667 	u16		data_len;
668 	compat_uptr_t	data;
669 };
670 
671 struct compat_ipmi_req {
672 	compat_uptr_t		addr;
673 	compat_uint_t		addr_len;
674 	compat_long_t		msgid;
675 	struct compat_ipmi_msg	msg;
676 };
677 
678 struct compat_ipmi_recv {
679 	compat_int_t		recv_type;
680 	compat_uptr_t		addr;
681 	compat_uint_t		addr_len;
682 	compat_long_t		msgid;
683 	struct compat_ipmi_msg	msg;
684 };
685 
686 struct compat_ipmi_req_settime {
687 	struct compat_ipmi_req	req;
688 	compat_int_t		retries;
689 	compat_uint_t		retry_time_ms;
690 };
691 
692 /*
693  * Define some helper functions for copying IPMI data
694  */
695 static long get_compat_ipmi_msg(struct ipmi_msg *p64,
696 				struct compat_ipmi_msg __user *p32)
697 {
698 	compat_uptr_t tmp;
699 
700 	if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
701 			__get_user(p64->netfn, &p32->netfn) ||
702 			__get_user(p64->cmd, &p32->cmd) ||
703 			__get_user(p64->data_len, &p32->data_len) ||
704 			__get_user(tmp, &p32->data))
705 		return -EFAULT;
706 	p64->data = compat_ptr(tmp);
707 	return 0;
708 }
709 
710 static long put_compat_ipmi_msg(struct ipmi_msg *p64,
711 				struct compat_ipmi_msg __user *p32)
712 {
713 	if (!access_ok(VERIFY_WRITE, p32, sizeof(*p32)) ||
714 			__put_user(p64->netfn, &p32->netfn) ||
715 			__put_user(p64->cmd, &p32->cmd) ||
716 			__put_user(p64->data_len, &p32->data_len))
717 		return -EFAULT;
718 	return 0;
719 }
720 
721 static long get_compat_ipmi_req(struct ipmi_req *p64,
722 				struct compat_ipmi_req __user *p32)
723 {
724 
725 	compat_uptr_t	tmp;
726 
727 	if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
728 			__get_user(tmp, &p32->addr) ||
729 			__get_user(p64->addr_len, &p32->addr_len) ||
730 			__get_user(p64->msgid, &p32->msgid) ||
731 			get_compat_ipmi_msg(&p64->msg, &p32->msg))
732 		return -EFAULT;
733 	p64->addr = compat_ptr(tmp);
734 	return 0;
735 }
736 
737 static long get_compat_ipmi_req_settime(struct ipmi_req_settime *p64,
738 		struct compat_ipmi_req_settime __user *p32)
739 {
740 	if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
741 			get_compat_ipmi_req(&p64->req, &p32->req) ||
742 			__get_user(p64->retries, &p32->retries) ||
743 			__get_user(p64->retry_time_ms, &p32->retry_time_ms))
744 		return -EFAULT;
745 	return 0;
746 }
747 
748 static long get_compat_ipmi_recv(struct ipmi_recv *p64,
749 				 struct compat_ipmi_recv __user *p32)
750 {
751 	compat_uptr_t tmp;
752 
753 	if (!access_ok(VERIFY_READ, p32, sizeof(*p32)) ||
754 			__get_user(p64->recv_type, &p32->recv_type) ||
755 			__get_user(tmp, &p32->addr) ||
756 			__get_user(p64->addr_len, &p32->addr_len) ||
757 			__get_user(p64->msgid, &p32->msgid) ||
758 			get_compat_ipmi_msg(&p64->msg, &p32->msg))
759 		return -EFAULT;
760 	p64->addr = compat_ptr(tmp);
761 	return 0;
762 }
763 
764 static long put_compat_ipmi_recv(struct ipmi_recv *p64,
765 				 struct compat_ipmi_recv __user *p32)
766 {
767 	if (!access_ok(VERIFY_WRITE, p32, sizeof(*p32)) ||
768 			__put_user(p64->recv_type, &p32->recv_type) ||
769 			__put_user(p64->addr_len, &p32->addr_len) ||
770 			__put_user(p64->msgid, &p32->msgid) ||
771 			put_compat_ipmi_msg(&p64->msg, &p32->msg))
772 		return -EFAULT;
773 	return 0;
774 }
775 
776 /*
777  * Handle compatibility ioctls
778  */
779 static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
780 			      unsigned long arg)
781 {
782 	int rc;
783 	struct ipmi_file_private *priv = filep->private_data;
784 
785 	switch(cmd) {
786 	case COMPAT_IPMICTL_SEND_COMMAND:
787 	{
788 		struct ipmi_req	rp;
789 
790 		if (get_compat_ipmi_req(&rp, compat_ptr(arg)))
791 			return -EFAULT;
792 
793 		return handle_send_req(priv->user, &rp,
794 				priv->default_retries,
795 				priv->default_retry_time_ms);
796 	}
797 	case COMPAT_IPMICTL_SEND_COMMAND_SETTIME:
798 	{
799 		struct ipmi_req_settime	sp;
800 
801 		if (get_compat_ipmi_req_settime(&sp, compat_ptr(arg)))
802 			return -EFAULT;
803 
804 		return handle_send_req(priv->user, &sp.req,
805 				sp.retries, sp.retry_time_ms);
806 	}
807 	case COMPAT_IPMICTL_RECEIVE_MSG:
808 	case COMPAT_IPMICTL_RECEIVE_MSG_TRUNC:
809 	{
810 		struct ipmi_recv   __user *precv64;
811 		struct ipmi_recv   recv64;
812 
813 		memset(&recv64, 0, sizeof(recv64));
814 		if (get_compat_ipmi_recv(&recv64, compat_ptr(arg)))
815 			return -EFAULT;
816 
817 		precv64 = compat_alloc_user_space(sizeof(recv64));
818 		if (copy_to_user(precv64, &recv64, sizeof(recv64)))
819 			return -EFAULT;
820 
821 		rc = ipmi_ioctl(filep,
822 				((cmd == COMPAT_IPMICTL_RECEIVE_MSG)
823 				 ? IPMICTL_RECEIVE_MSG
824 				 : IPMICTL_RECEIVE_MSG_TRUNC),
825 				(unsigned long) precv64);
826 		if (rc != 0)
827 			return rc;
828 
829 		if (copy_from_user(&recv64, precv64, sizeof(recv64)))
830 			return -EFAULT;
831 
832 		if (put_compat_ipmi_recv(&recv64, compat_ptr(arg)))
833 			return -EFAULT;
834 
835 		return rc;
836 	}
837 	default:
838 		return ipmi_ioctl(filep, cmd, arg);
839 	}
840 }
841 
842 static long unlocked_compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
843 				       unsigned long arg)
844 {
845 	int ret;
846 
847 	mutex_lock(&ipmi_mutex);
848 	ret = compat_ipmi_ioctl(filep, cmd, arg);
849 	mutex_unlock(&ipmi_mutex);
850 
851 	return ret;
852 }
853 #endif
854 
855 static const struct file_operations ipmi_fops = {
856 	.owner		= THIS_MODULE,
857 	.unlocked_ioctl	= ipmi_unlocked_ioctl,
858 #ifdef CONFIG_COMPAT
859 	.compat_ioctl   = unlocked_compat_ipmi_ioctl,
860 #endif
861 	.open		= ipmi_open,
862 	.release	= ipmi_release,
863 	.fasync		= ipmi_fasync,
864 	.poll		= ipmi_poll,
865 	.llseek		= noop_llseek,
866 };
867 
868 #define DEVICE_NAME     "ipmidev"
869 
870 static int ipmi_major;
871 module_param(ipmi_major, int, 0);
872 MODULE_PARM_DESC(ipmi_major, "Sets the major number of the IPMI device.  By"
873 		 " default, or if you set it to zero, it will choose the next"
874 		 " available device.  Setting it to -1 will disable the"
875 		 " interface.  Other values will set the major device number"
876 		 " to that value.");
877 
878 /* Keep track of the devices that are registered. */
879 struct ipmi_reg_list {
880 	dev_t            dev;
881 	struct list_head link;
882 };
883 static LIST_HEAD(reg_list);
884 static DEFINE_MUTEX(reg_list_mutex);
885 
886 static struct class *ipmi_class;
887 
888 static void ipmi_new_smi(int if_num, struct device *device)
889 {
890 	dev_t dev = MKDEV(ipmi_major, if_num);
891 	struct ipmi_reg_list *entry;
892 
893 	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
894 	if (!entry) {
895 		printk(KERN_ERR "ipmi_devintf: Unable to create the"
896 		       " ipmi class device link\n");
897 		return;
898 	}
899 	entry->dev = dev;
900 
901 	mutex_lock(&reg_list_mutex);
902 	device_create(ipmi_class, device, dev, NULL, "ipmi%d", if_num);
903 	list_add(&entry->link, &reg_list);
904 	mutex_unlock(&reg_list_mutex);
905 }
906 
907 static void ipmi_smi_gone(int if_num)
908 {
909 	dev_t dev = MKDEV(ipmi_major, if_num);
910 	struct ipmi_reg_list *entry;
911 
912 	mutex_lock(&reg_list_mutex);
913 	list_for_each_entry(entry, &reg_list, link) {
914 		if (entry->dev == dev) {
915 			list_del(&entry->link);
916 			kfree(entry);
917 			break;
918 		}
919 	}
920 	device_destroy(ipmi_class, dev);
921 	mutex_unlock(&reg_list_mutex);
922 }
923 
924 static struct ipmi_smi_watcher smi_watcher =
925 {
926 	.owner    = THIS_MODULE,
927 	.new_smi  = ipmi_new_smi,
928 	.smi_gone = ipmi_smi_gone,
929 };
930 
931 static int __init init_ipmi_devintf(void)
932 {
933 	int rv;
934 
935 	if (ipmi_major < 0)
936 		return -EINVAL;
937 
938 	printk(KERN_INFO "ipmi device interface\n");
939 
940 	ipmi_class = class_create(THIS_MODULE, "ipmi");
941 	if (IS_ERR(ipmi_class)) {
942 		printk(KERN_ERR "ipmi: can't register device class\n");
943 		return PTR_ERR(ipmi_class);
944 	}
945 
946 	rv = register_chrdev(ipmi_major, DEVICE_NAME, &ipmi_fops);
947 	if (rv < 0) {
948 		class_destroy(ipmi_class);
949 		printk(KERN_ERR "ipmi: can't get major %d\n", ipmi_major);
950 		return rv;
951 	}
952 
953 	if (ipmi_major == 0) {
954 		ipmi_major = rv;
955 	}
956 
957 	rv = ipmi_smi_watcher_register(&smi_watcher);
958 	if (rv) {
959 		unregister_chrdev(ipmi_major, DEVICE_NAME);
960 		class_destroy(ipmi_class);
961 		printk(KERN_WARNING "ipmi: can't register smi watcher\n");
962 		return rv;
963 	}
964 
965 	return 0;
966 }
967 module_init(init_ipmi_devintf);
968 
969 static void __exit cleanup_ipmi(void)
970 {
971 	struct ipmi_reg_list *entry, *entry2;
972 	mutex_lock(&reg_list_mutex);
973 	list_for_each_entry_safe(entry, entry2, &reg_list, link) {
974 		list_del(&entry->link);
975 		device_destroy(ipmi_class, entry->dev);
976 		kfree(entry);
977 	}
978 	mutex_unlock(&reg_list_mutex);
979 	class_destroy(ipmi_class);
980 	ipmi_smi_watcher_unregister(&smi_watcher);
981 	unregister_chrdev(ipmi_major, DEVICE_NAME);
982 }
983 module_exit(cleanup_ipmi);
984 
985 MODULE_LICENSE("GPL");
986 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
987 MODULE_DESCRIPTION("Linux device interface for the IPMI message handler.");
988 MODULE_ALIAS("platform:ipmi_si");
989